Method and means of electrodeposition



Patented F b. 4, 193s METHOD AND MEANS or anac'rao- DEPOSITION Paul R. Pine, Elyria, Ohio, assignor to The Barshaw Chemical Company,

poration of Ohio No Drawing.

Elyria, Ohio, a cor- Application May 4, 1934,

Serial No, 123,951

12 Claims.

There have been known for some time several agents which as added to certain plating baths, improve the quality and character of the deposited metal. With these, limitations of one 5 kind or another have been usual, and each metal or bath has raised its own problems. I have now found however, that a bath constituent applicable to a wide range of metals and conditions, is possible, and with production of'metal deposits of excellent brightness, ductility, freedom from pin holes, and pitting.

To,the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described, and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative however, of but a few of the various ways in which the principle of the invention may be employed. In accordance with the invention, I provide an electrolytic bath including an addition agent which is a sulphuric acid reaction product of such compound .as a terpene, including hemiterpenes, sesquiterpenes, di-terpenes, polyterpenes, their derivatives, and related resins and oleo resins, and for conciseness, all such compounds and their synthetic analogues may be conveniently referred to as organic compounds having substantially a terpenic type nucleus. In-

stances of these are for example, terpenes as dipentene or racemic limonene, dextro and laevolimonene, sylvestrene or carvestrene, carene from long leaf pin oil, pinenes, as from various turpentine oils, phellandrenes, menthene,

terpinolene, camphene, bomylene, etc.; hemiterpenes, as isoprene, piperylene, etc.; sesquiterpenes, as caryophyllene, cadinene from sandalwood, gurjunene as from gurjun balsam oil, santalene, c'adinene as from oil of cubebs, selinene, etc.; di-terpene, as in rosin oil; poly terpenes, as rubber, balata, gutta percha, etc.; terpene alcohols, as tcrpineol, borneol, isoborneol, beta-terpineol as from yellow pine oil,

fenchyl alcohol, geraniol','linalool, laevo-menthol,

etc.; terpene aldehydes, as citral, citronellal, etc.; terpene ketones as camphor, 'fenchone, piperitone, racemic pipertone as from eucalyptus'oil, .menthone, thujone, pulegone, 'carvone, etc.; de-

rivatives of terpenes, as terpin hydrate, geranic acid, camphenic acid, abietene, isoborneol acetate, borneol chloride, pinene hydrochloride, camphor oxime, isonitrosocamphor, sylvestrene nitrosate, ,pyrolytic products of rubber or of resins; resins generally,,as-kaurl, Zanzibar and other African.

alpha copals,-Manila copal, damar, masticfsandarac, acaroid, dragons blood, shellac, rosin, etc.; oleoresins or balsams, as Oregon balsam from Douglas fir, Canada balsam, Peru balsam, balsam of Tolu, copaiba, gurjun, etc.; terpene-contain- 5 ing oils, as rosin oil, turpentine, Venice turpentine, pine oil, copaiba oil, cedarwood oil,'etc. The preparation of the reaction product not being part of the present invention, is immaterial as to its detail, and it is sumcient to here say that it 10 may have geen prepared in any known or preferred way, such as by treating the turpenoid with sulphuric acid, fuming sulphuric acid, sulphur trioxide, halogen sulphonic acids, sulphuryl halides, alkyl or aryl hydrogen sulphates, dialkyl 15 sulphates, sulphur dioxide and air in the presence of metal oxides or salts, or any of the preceding agents in combination with a reaction promoter such'as salts of iron, copper, mercury, boric acid, aluminum halides, etc.; and further- 20 more, the sulphuric acid reaction product may if desired, be neutralized with a base, as an alkali metal compound, such as sodium hydroxide, or the metal or a compound of the metal to be electrodeposited; and for illustration, in order to 25 make the nature of the addition agents wholly clear, an agent may be employed which has been prepared as follows: 100 parts by weight of alphapinene is slowly added to 350 parts of 10 per cent oleum or fuming sulphuric acid, preferably with 30 continuous stirring and cooling as necessary to .as an addition agent to metal plating baths genbelow C. The alpha-pinene being added within a period of one-half hour or less, the mixture is heated to about C. for approximately 4 hours. The resulting product is soluble in 35 water except for a very small residue, and may be employed in the plating bath as such, or may be neutralized by slow admixture of 30 per cent caustic ,sodasolution, with cooling if necessary, to maintain the temperature below about 85 0., and 40 the neutralization being stopped desirably just short of neutral point on the acid side. The solutlon, if a dry productis desired, may then be concentrated, as on a steam bath, and is available 45 erally, such as with copper, nickel, zinc, cadmium, tin, etc; Similarly, as another illustration, a product may be employed which has been prepared as follows: 280 parts by weight of rosin oil, de-acidifled, such asfrom pale London 011, 50 are slowly added to 700 parts of 20 per cent oleum, with stirring and cooling, as necessary, to maintain a temperature below about 60 C. The rosin oil being added within one-half hour or less, the mixture is heated, preferably with stirring, 55

for an hour or more to'about 80 C. The prodnot is water-soluble except for a very small amount of residue, and may be employed as such,

or may be neutralized to a salt, as for instance 5 by addition of a 25 per cent suspension of nickel carbonate in water. The resultant solution may be concentrated, as on a steam bath, to a soft, crumbly solid, as an addition agent for nickel plating. While as indicated, neutralization of the sulphuric acid reaction product may be stopped short of neutral point on the acid side, the addition of the neutralizing material may be carried just to the neutral point or beyond, as desired or the un-neutralized sulphuric acid reaction product may be added to the platingbath and the pH of the bath may be adjusted to any desired value by known methods.

The amount of the control agent or addition agent added to the electro-deposition bath may vary somewhat with circumstances and require ments in view, ranging'for instance from about 0.01-2 oz. per gallon. Amounts thereabove are not necessary in general. Either acid or alkaline .baths may be thus treated, and such operation is advantageous with various metals in wide range,

as copper, nickel, zinc, cadmium, tin. etc.

' As readily understood also, the ester salts of any of the terpenoids, as designated, may be employed, some being more conveniently commercially attainable than others. In general, sulphuric acid reaction products of such compounds as dipentene, pinene, oil of turpentine, caryophellene, abietene, rosin, gum damar, acid free rosin oil, etc., are particularly available conveniently.

As examples, there may be noted:

Oz.persal.

I. ZnSO4 32-48 ZnCh 3-12 Sodium acetate 2- 8 4o Boric acid 2- 6 Sulphuric acid reaction product or terpenoid 4 Sulphuric acid is added to a concentration 01' 10 per cent.

The current density may be 10-100 amp. per

square foot, and the temperature 30-35 C.

Oz. per ml. 4 II. NlSOr 20 N101: 3

H330: 4.4 Sulphuric acid reaction product of terpen'oid 6 NiCOa is added to a pH 01' 2.5 to 3.

The temperature may be 40-45 0., and the current density 10-30 amp. per square foot.

, Oz. per gal.

, In. CdO .V -IO NaCN -2 -22 NMCO: 2

Salt of sulphuric acid reaction product of terpenoid .01- 4 Operating this bath at room temperature up to' 35 0., a current density 01' 15-50 amp. per square foot yields excellent results, 'with clear, mirrorlike deposits and smooth surface.

pergal. IV. CdSO4 Si -24 CdCh 2: -12

330: 2 8 Salt of sulphuric acid reaction product or terpenoid. .01- 8 The pH may be 3-5 and operation may be car- I foot.

rled on at room temperature and with current density of 10-30 amp-per square foot, with excellent results.

, Oz. per gal. V. NiSOi' 5 -45 5 NiCla 2 8 H3303 3 5.5

Salt of sulphuric acidreaction product of terpenoid .0142

The pH may be 1.0-6.5, and cathode current 10 density 5-100 amp. per square foot.

. Oz. per gal. VI. Ni$04 12 -24 NiCla 2 6 H3303 2 5.5 1 Salt of sulphuric acidreac on product of terpenoid .01- 8 Operation may be carried on at room temperature, and with pH of 1.0-6.5,and cathode current 20 density 5-25 amp. per square foot.

' Oz. per gal. VII. CuSOr 20 -33 H2304 6 -12 Salt'of sulphuric aid reaction 25 product of terpenoid .01- 4 The temperature may be 35-45 C., and a current density of 10-150 amp. per square foot may be employed.

1 Oz. per 'gal. 30 CuCn 2 8.5

' NaCn 3 -16 NazCOr 2 NazSO: 1% 86 Salt of sulphuric acid reaction product of terpenoid .01- 3 The current density may be 10-45 amp. per square foot.

I Oz. per gal. 0 IX. ZnSOr 30 -50 ZnCh 3 8 H2303 2 6 Salt of sulphuric acid reaction Operation may be at room temperature and with current density of 5-60 amp. per square The invention is characterized by a widespread versatility oil-application irrespective of 'the'ibath reaction or character, and with suit- 00 able conditions, high deposition rates may be carried on without'dimculty, and with attainment of attractively smooth, bright metal surfaces, and excellent metal texture.

This application is a continuation-impart of 05 my prior application Serial No. 695,328, fi led October 26th, 1933. Other modes of applying the principle oi the invention may be mployed, change being made as regards the details described, provided the features stated in any of the following claims, or

r the equivalent of such, be employed.

I therefore particularly point out and distinctly claim as my invention: 1

. 1. An electro-depositing bath, comprising a solution of a compound of a metal to be deposited by electrolysis, and a sulphuric acid reaction l product of an organic compound having substantially a terpenic type nucleus, said reaction product having been pre-formed.

2. An electro-depositing bath, comprising a solution of a compound of a metal to be deposited by electrolysis, and a sulphuric acid reaction product of dipentene, said reaction product having been pre-formed.

I 3. An electro-depositing bath, comprising a solution of a compound of a metal to be deposited by electrolysis, and a sulphuric acid reaction product of pinene, said reaction product having been pre-formed.

4. An electro-depositing bath, comprising a solution of a compound of nickel to be deposited by electrolysis, and a sulphuric acid reaction product of an organic compound having substantially a terpenic type nucleus, said reaction product having been pre-formed.

5. An electro-depositing bath, comprising a solution of a compound-of nickel to be deposited by electrolysis, and a sulphuric acid reaction product of dipentene, said reaction product having been pre-formed.

6. An electro-depositing bath, comprising a solution of a compound of nickel to be deposited by electrolysis, and a sulphuric acid reaction product of pinene, said reaction product having been pre-formed.

7. A process of eiectro-deposition, which comprises electro-depositing a metal from a solution 01 a compound of the metal, there being added to such solution a sulphuric acid reaction product 'of an organic compound having substantially a terpenic type nucleus.

8. A process of electro-deposition, which comprises electro-depos1tinga metal irom a solution of a compound of the metal, there being added to such solution a sulphuric acid reaction product of dipentene.

9. A process of electro-deposition, which comprises electro-depositing a metal from a solution of a compound of the metal, there being added to such solution a sulphuric acid reaction product of pinene.

10. A process of electro-deposition, which comprises electro-depositing nickel from a solution of a compound of the nickel, there being added a sulphuric acid reaction product of an organic compound having substantially a terpenic type nucleus.

11. A process of electro-deposition, which comprises electro-depositing nickel from a solution of a compound of the nickel, there being added a sulphuric acid reaction product of dipentene.

12 A process of electro-deposition, which comprises electro-depositing nickel from a solution of a compound of the nickel, there being added a sulphuric acid reaction product of pinene.

PAUL R. PINE. 

